2010 S80 Air Gulping...

erocki · Post by **erocki** » 31 Oct 2015, 15:38

I have a question about normal sounds. I have a 2010 S 80 3.2L running great but a couple of things have started happening and I wanted your guys expertise. First, I notice that that when I apply gas even slightly while idle, I hear a gulping of air sound coming from near the intake manifold. It is just a quick gulp of air but wasn't sure if this is normal or if I have a leak.

Second, I noticed a slight slipping of the trans between second and third...kind of a hover and then bump engage. It doesn't do it all time, but definitely noticed. Any known issues or fixes that you can recommend?

Thanks in forward...

Post by **jimmy57** » 01 Nov 2015, 09:02

The gulping is not unusual. The vacuum pump for the brake booster is on the engine. When you pump brakes on each release of pedal the pump has a lot of air to displace to refill booster with vacuum. The pump discharges air into inside of engine. The crankcase vent system has a valve that can burp when this all happens.

Do a couple of drain and refills on the trans and see if the shifting returns to normal.